Gas water heater



FIG. 1 is a front elevation view of our design for a gas water heater;

FIG. 2 is a rear elevation view thereof;

FIG. 3 is a right side elevation view thereof;

FIG. 4 is a left side elevation view thereof;

FIG. 5 is a top, plan view thereof;

FIG. 6 is a bottom view thereof; and,

FIG. 7 is a top, front, and right side perspective view thereof. 

The ornamental design for a gas water heater, as shown and described. 